$10K ? Having never made one of these, this may seem out of line, but one can get an aluminum head for way under that, under $1,000 and that is for a production run under 10 where the universal supply and demand is incredibly limited. My guess is that a head is much more complicated than a bell housing. Assuming the costs are much lower, is there anyone out there able to advise if the bell housing is the major factor / major part?

Many factors. Yes a head is more complicated. Time is also a factor. I think one bellhousing I did some design work cast $35K to cast prototypes. Due to time constrianst, it was needed in two weeks. Usual time is about a month. Also, were the part is cast. China is much cheaper, at least at the moment. So, we are comparing a price for a prototype to a limited production. Cost should be simular, but I'd think somewhat less for a production part.
Still, I was pointing out that the main cost would be the initial casting cope and drag or forms.
Tom

I 2nd this. I have some experience with plastic roto-mold construction, and even though its a totally different medium, the construction of a precision mold is not cheap. 10 to 20K minimum, and that would be a much simpler mold than something for cast aluminum.

Also, question on the custom head. For a custom head, would it not be completely machined out of a block of aluminum? I figure for something like that you would start with a blank of raw material, and machine it to specs, you wouldn't be casting something new first I don't think.

To cast a complete bell housing, you need to create a complex mold, followed by lengthy machining process. By the time you are done, it would be 20-30 times the price than just adapting something else, or another chassis transmission to the application.

Im not sure its a totally realistic idea for this, you would need a very large group of people to pony up a very large collection of cash for an extremely complex, completely untested product that requires many many steps in construction.

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It really depends on the market. Many prototype heads are cast. Some of that is to check out how it would hold up for production. Also, at a certain point it is more cost effective to cast, than machine even in low volumes. Depends on size and complexity of the part. My overall point is that there is an itnital cost with casting, ie the molds. That cost has to be amortized over the lot or number of produced units. The cost of machine a flywheel housing as I remeber wasn't very cost prohibative. Still the $600 offer on the table has scared many away. It is probably fairly reasonable, given low volume etc. There was talk about importing trans from India. I don't know if any figures ever came of that.
Tom

For an adapter, sure. I wouldnt hesitate to pay 2 times that for a rebuilt 5 speed. Brand new with warranty from ZF? I'd waste some loot on that.

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